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Salmon Says, an Anti-Cancer Investigation: Part 3. Radiation and the Wild Pacific

Author’s Note: This piece was posted in March 2012. Since that time, we have been learning more and more about the extent of damage caused by the March 2011 Fukushima disaster. I am revisiting the effects of that devastating incident on our Pacific Ocean fish supply and will update that info periodically.

SUMMARY So far, in this anti-cancer investigation, we’ve been talking about pollutants from industry, which concentrate in fat. Our conclusions:

Salmon from the Bering Sea in Alaska win top prize. Next best: salmon from southern Alaska and British Columbia (except for certain species that reside in the dirty Strait of Georgia.) For you salmon lovers, pink followed by sockeye are top choices: You can eat quite a bit without consuming too much of the bad stuff.

But what about radiation in your wild Pacific salmon, which seek out the bones and muscle? Is that a concern?

INTRO

For all those years (mid 40s to the 80s), the Pacific Ocean was the site of nuclear testing. Even “pristine” Alaska wasn’t spared– nuclear testing near the Aleutians, nuclear subs still decaying in the sea, fallout from the Chernobyl disaster that made its way north. Is there radiation in our wild Pacific salmon?

All wild Pacific salmon native to North America are very clean from a radiation standpoint, says Jarvis Caffrey, a radiation health specialist at Oregon State University. In fact, experts agree that up to now, most Pacific fish have been, radiation-wise, quite clean. The reason? Pacific Ocean currents are so strong and waters, vast that radiation gets extremely diluted.

BUT WHAT ABOUT FUKUSIMA? Will history’s largest accidental deposit of radiation in the ocean affect our salmon?

Caffrey has been part of an international research team tracking the trails of Fukushima In the Pacific. Understandably, he is more worried about the food supply for the unfortunate Japanese. All the evidence from Fukushima thus far shows that the effect is localized to Japanese waters.

And what are the specific concerns? When it comes to radiation in the waters, cesium- 134 and 137 are among the key elements. They stick around much longer than the short lived radioactive iodine you’ve heard about–134 for about two decades; 137 for about 300 years. (A general rule of thumb: Radionuclides remain in the environment for about 10 times their physical half lives.) These elements travel in water, with the currents, and in air, thus getting deposited in rain, and cesium-137, along with strontium-90, can both accumulate in fish. Then there’s plutonium, which can stick to particles that settle on the sea floor or to the sediments directly. Plutonium is highly reactive.

WHAT ARE SCIENTISTS FINDING?

Caffrey’s team—led byDr. Ken Buesseler,a senior scientist at the Woods Hole Oceanographic Institution in Massachusetts and a world expert in marine radioactivity—as well as other researchers have tracked radiation up to 600 kilometres (400 miles) off Japan’s coastline. The amount they’ve found thus far does not pose a risk to humans or marine life, they say. “The levels we measured are below those thought to be of concern to humans for risk of cancer or other radiation effects,” says Buesseler. In fact, that appears to be the common opinion among scientists, althougha few scientific voices are raising doubts.

But Buesseler says there is a problem: The radioactivity levels in the ocean at the power plant have not been declining in recent months. And if the surrounding waters are not clean enough, then the radioactive elements in the fish and plants will remain elevated.

As they readily admit,they’ve detected levels of radiation higher than their standards in many seaweed and fish located near the reactor.The sand lance, for example, which lives on the coastal surface and is used to make fish feed, was among the first organisms in which excess radiation was detected. The seabass–a species that dwells in the mid-level waters—also revealed high levels.

As for Japan’s salmon, so far, excess levels of radiation have only shown up in their land-locked species. (Freshwater fish have a harder time eliminating radioactive matter than saltwater species, and the material takes time to accumulate in saltwater fish that eat higher on the food chain.)

Scientists agree, however, and the Japanese numbers suggest, that the biggest concern at this point are the fish that feed on sediments at the bottom of the sea (the benthic zone), including flounder and greenling, along with filter feeders such as mussels and clams, which take in food by filtering water and accumulate toxins.

Will any of these contaminated plants or fish in time work their way up the food chain or directly onto somebody’s plate? Let’s look at that possibility.

But Japan is still exporting some fish. From where? It’s hard to know. Japan’s ban on fishing only covers an area 30 kilometres from the site, and nobody seems to know much more than that about where the fish are coming from—not the FDA, not the Canadian Food Inspection Agency. Both Canada and the US are still importing Japanese foods, including fish from their seas.

Right after the incident, the Canadian Food Inspection Agency ( CFIA) launched an emergency plan–a sampling and testing strategy to monitor radiation in Japanese products. All food products they tested were“well below Health Canada’s actionable levels for radioactive material,” they say. In June, 2011, they discontinued that plan. Since then, products from Japan have been getting the same scrutiny as products from elsewhere. The government still monitors radiation in imported foods to the same degree it did prior to the disaster; at this point they have no plans for additional testing of foods from Japan.

And the FDA? Since March 2011, the FDA has tested 199 samples of seafood coming in from Japan (including one salmon product) and performed field exams, using radiation detectors, on 40 percent of the seafood products entering the US. To date, nothing has been of concern.

Almost 200 samples in 14 months, amid reports that radiation levels are not declining? Does that put you at ease to eat foods from Japan ?

Neither the radiation carried through ocean currents nor the radiation carried through atmospheric currents and deposited via rainfall in North America and the Pacific is a problem, they say. (The report is dated January 2012 although much of the evidence it relies on is from the early days of the disaster.)

But the authors do raise this possibility: Migratory fish from Japan or from elsewhere in the Pacific could feed in contaminated waters and then swim to US or Canadian waters and get caught. Albacore tuna and salmon, they say, are two potential culprits.

SALMON: IS THERE A PROBLEM?

In the case of wild Pacific salmon from the US and Canada, you have nothing to worry about, says Dr. David Welch, a world expert on salmon migratory patterns. Salmon from Japan do not migrate as far as the North American coast, he says, and likewise, our North American species do not migrate as far west as Japan’s coastal waters.

Other migratory species, however, including mackerel as well as tuna, may be more cause for alarm. Should our governments be concerned about that?

WHAT’S COMING OUR WAY? THE KUROSHIO CURRENT

You have to seethis map —a moving projection of the Kuroshio current, a strong ocean current that flows eastward off the coast of Japan and could be carrying many of the longer-lived radioactive elements. The current moves toward the US Pacific coast (in fact, it kept the radiation from travelling southwards), then mixes with another current and moves up to Alaska. The elements in the current are projected to arrive near the US west coast in about 4 years.

(Don’t confuse this with the debris you’ve seen;that gets pushed along faster by the wind. In fact some of it has already arrived, but many experts say it probably doesn’t present a radiation problem : The tsunami pushed the debris offshore before most of the radiation was released. )

By the time any Fukushima elements arrive here in that current, Caffrey says, they will be so diluted as to have no effect. Virtually all scientists agree.

Meanwhile, could our fish become contaminated by feeding in that current—or by feeding on fish that have fed there? Again, Welch is not concerned about our salmon. “ Nothing we currently know about salmon suggests that any North American salmon go anywhere close to the areas of higher radiation levels,” he says.

THE BOTTOM LINE ON YOUR WILD PACIFIC SALMON

No radiation worries for now, but if you’re shopping for salmon or eating in a restaurant, you might want to make sure you’re not getting the Japanese version. (“Cherry” salmon is the species there.) As for other fish, I’m on the case. Will this bring a whole new meaning to the term “Watergate”? Click onthis linkif you’re too young to remember.Follow this blogfor continual updates.

NEXT: Now that we’ve settled on what wild Pacific salmon to ask for, how does farmed Atlantic salmon compare? Are the concerns that surfaced in the mid 2000s about PCBs in farmed Atlantic salmon still valid? Is “organic” farmed salmon a better choice?

3 thoughts on “Salmon Says, an Anti-Cancer Investigation: Part 3. Radiation and the Wild Pacific”

I was looking at a piece of bone in some soup I made using canned pacific salmon, and it looked pockmarked with holes. I then googled bone cancer and the images I saw of bones affected by cancer and osteoperosis appeared similiar to this large piece of bone in my soup.

I have been making this soup for a long time now, prior to the events at Fukushima, and I don’t recall having seen these soft bone pieces that come in these cans of pink salmon ever looking like that before.

Have you guys tried testing a can of Clover Leaf salmon for signs of caesium or strontium or any of the ohter long-lived particles that might be entering the food chain as a result of the disaster in Japan?

People should know for certain and more warnings should be put out, people haven’t stopped eating the fish, when perhaps it’s vital that they do now. Thank you

Nuclear engineer and Fukushima watchdog Arnie Gunderson, http://fairewinds.org/, recently told me that he has tested Alaskan salmon for radionuclides released by Fukushima, and the salmon was clean. I will continue to monitor the issue.